1. Field of the Invention
The subject invention is generally related to a device for determining the water depth of fishing lures and the like and is specifically directed to an on-line indicator for monitoring the depth of fishing bait as it is pulled through the water.
2. Description of the Prior Art
With the development of electronic devices for determining water depth and determining the location of objects in the water, numerous electronic systems have been developed to aide fishing enthusiasts in locating and catching fish. For example, "fish finders" are well known and are used to determine the location of schools of fish in a body of water. The more sophisticated fish finders not only locate the school but indicate the depth of the school within the specific location. It is common to troll crank bait, lures and other baits through the water in the vicinity of the school in an effort to attract the fish toward the bait and draw a strike. Typically, this is accomplished by paying out a specific amount of fishing line from a rod and reel located within a boat and then trolling the boat across the surface of the water in the vicinity of the school at a specific speed.
It is common knowledge that different types of bait, dependent on configuration, weight, hydrodynamics and other factors will troll through the water at different, predictable depths. The depth of the bait being pulled through the water is also dependent upon the amount of line paid out from the rod and the speed at which the boat is trolling through the water. It is desirable to know with certainty at what depths specific baits will troll through the water under predefined conditions. For example, if a school of fish is found to be at eight feet below the surface of the trolling boat, it is advantageous to know what bait can be secured to the line to troll through the water in the vicinity of eight feet, greatly increasing the chances for drawing fish toward the bait. In a typical example, if 200 feet of line is paid out from the boat and the boat is trolling through the water at three miles per hour, specific baits will troll through the water at a predetermined and predictable depth. In the past, the depth of the bait has been determined through trial and error and at best the results have been less than accurate. However, detailed log books have been created cataloging the performance of various baits under controlled conditions. Tournament participants, in particular, have relied on these log books in an effort to use bait consistent with the conditions in an effort to obtain predictable results. Such efforts have met with spotty success.
While various water depth monitoring devices have been available, there are no known devices specifically dealing with this subject problem. That is, there are no known devices in the prior an for monitoring the depth at which specific baits operate under predetermined, controlled conditions.
Examples of depth indicators for use in sport fishing, tournament fishing and the like are shown, for example, in U.S. Pat. No. 2,821,805 issued to W. Kunze on Feb. 4, 1958 and U.S. Pat. No. 3,038,143 issued to W. Dow on Jun. 5, 1962. The Kunze patent discloses a fish finding apparatus having a depth gauge attached to a net and adapted for pulling the net through the water at a specific depth in order to increase the chances that the net will be pulled through a school of fish. The Dow patent discloses a telemetering depth meter and a hydrophone adapted for pulling a net through the water at a specific depth. Both the Kunze and Dow patents are particularly suited for commercial fishing. Neither of these devices is readily capable for sport fishing and is not adaptable for determining the operating depth of specific baits.
Examples of depth sensitive transducers are shown in U.S. Pat. No. 3,308,425 issued to McLoad on Mar. 7, 1967; U.S. Pat. No. 4,225,952 issued to Lewis on Sept. 30, 1980; U.S. Pat. No. 4,926,397 issued to Robertson on May 15, 1990; and U.S. Pat. No. 4,943,951 issued to Leavell et al on Jul. 24, 1990. Each of these patents discloses various circuitry and devices for measuring water depth through utilization of a pressure transducer or the like. Examples of depth indicators for use by boaters and divers are disclosed in U.S. Pat. No. 2,774,881 issued to Rich on Apr. 13, 1954 and U.S. Pat. No. 3,857,283 issued to Jennings et al on Dec. 31, 1974, respectively.
While depth finding apparatus are well known, none of the art discloses a device which is specifically directed to determining the performance of fishing bait pulled through the water by a moving fishing line in a trolling operanon.